1. Field of the Invention
This invention relates to a new tensioner for a power transmission belt or the like and to a new method of making the same.
2. Prior Art Statement
It is known to provide a tensioner for a power transmission belt that is adapted to be operated in an endless path, the tensioner comprising a support means for being fixed relative to the belt, a belt engaging means carried by the support means and being movable relative thereto, first spring means operatively associated with the support means and the belt engaging means for urging the belt engaging means relative to the support means and against the belt with a force to tension the belt, and frictional dampening means operatively associated with the support means and the belt engaging means to dampen the movement of the belt engaging means relative to the support means in at least one direction of movement thereof, the dampening means having a longitudinal axis, the support means comprising a shaft means having a longitudinal axis and being fixed from movement relative to the belt engaging means, the belt engaging means having a portion thereof being rotatably carried by the shaft means so as to rotate relative to the shaft means, the dampening means comprising a pair of frictionally engaging first and second parts with the first part comprising an annular pad of friction material that is coaxially disposed and axially movable on the shaft means relative to the second part, and second spring means urging the first part against the second part with a certain spring force, the first part of the dampening means having guide means thereon, one of the support means and the belt engaging means having opening means therein that receive the guide means therein to guide axial movement of the first part. For example, see the Henderson U.S. Pat. No. 4,596,538.
It is also known to provide a cup-shaped bushing of polymeric material between a belt engaging arm and an end plate of a support means to provide for rotational movement of the belt engaging means relative to the end cap of the support means, the cup-shaped bushing having the tubular sleeve portion thereof being loosely disposed between the outer peripheral surface of the end plate and a concentrically disposed part of the belt engaging arm.